Where can I find online primary sources for history?
Uh ... a library?
What particular history topic? And what class level - High School, University?
College level, North America or the United States, between 1600 and 1877.
https://www.loc.gov/topics/americanhistory.php (some good resources there)
The US national (government) archives may also provide information.
US History is strongly tied to British and European history, particularly prior to 1800.
I would imagine most university history departments could recommend some history textbooks.
I also think you should go online. There you can get lots of useful links regarding the topic. There are also online libraries available on some sites, you can search over there.
College as post secondary school education (after 17/18)? Or college also meaning High School in NZ/Australia etc?
What specific information about North America or the US between that period is needed? If you were given a course outline (only if you aren't at High School level) which contained a reading list, I would utilise that. Also using the library can be a good thing. Don't have in your bibliography all these URL's (http://owll.massey.ac.nz/referencing/apa-interactive.php).
Or the correct address, which is www.archive.org
Separate names with a comma.